Dozens of ambulances with their sirens blaring raced to the scene of the incident, which occurred yesterday on a narrow bridge to an island in Phnom Penh where festivities were being held to mark the end of the annual event.
Prime Minister Hun Sen described it as Cambodia’s darkest hour since the Khmer Rouge, whose 1975-1979 rule left up to a quarter of the population dead.
“This is the biggest tragedy since the Pol Pot regime,” Hun Sen said in a live television broadcast, referring to the Khmer Rouge’s late leader.
He said Cambodia would hold a national day of mourning on Thursday.
The stampede left at least 345 people dead and 410 injured, a government spokesman told AFP.
“Most of the deaths were as a result of suffocation and internal injuries,” Khieu Kanharith said.
It was not clear what triggered the stampede, but he said a rumour had spread among the revellers that the bridge was unstable.
“So panic started. It was too crowded and they had nowhere to run,” he said.
Witnesses reported people pushing and shoving in the crowd.
“We were crossing the bridge to Diamond Island when people started pushing from the other side. There was lots of screaming and panic,” 23-year-old Kruon Hay told AFP at the scene. “People started running and were falling over each other. I fell too. I only survived because other people pulled me up. Many people jumped in the water.”
Police were seen carrying away some of the victims while others were laid in a row on the ground. Many of the dead appeared to be young Cambodians.
Dozens of people gathered outside the city’s Calmette hospital, where at least 105 people were confirmed dead, according to a police officer.
More bodies were taken to other hospitals across the city, he said.
Many festivalgoers were in tears after the tragic end to the three days of boat races, concerts and fireworks.
The annual festival, one of Cambodia’s largest and most exuberant, marks the reversal of the flow between the Tonle Sap and Mekong rivers. It is also seen as a way of giving thanks to the river for providing fertile land and abundant fish.